The present invention relates generally to chains, and more particularly to link chains.
There are already known various constructions of link chains, such as lug chains, harness chains, flyer chains and roller chains, among them such which include a plurality of mutually hingedly interconnected chain links each of which has two lateral walls which extend in the longitudinal direction of the chain and are spaced from each other transversely of the chain. Then, a bearing pin is arranged at one end region of each of the lateral walls, such bearing pins being aligned with one another. However, chains of this construction exhibit a relatively complicated construction and are thus correspondingly expensive. Furthermore, such known chain constructions can be deviated only slightly in the transverse direction, so that they are, for instance, not suited for three-dimensional advancement, among others, also not for their arrangement on chain drums which are intended to wind up chains in a helical fashion. Also, the guidance of chains of the above type on sprocket wheel is not particularly good.
There is already known, for instance from the PCT application No. WO 85/01783, a link chain whose links are made of elastic synthetic plastic material. The respective chain link of this chain has two lateral walls which extend in the longitudinal direction of the chain and which are rigidly connected at one of their ends by a bearing sleeve, while each of them is provided at its other end with a respective bearing pin. These bearing pins are aligned with one another and they are directed toward each other. The lateral walls can be elastically bent in the outward direction to such an extent that these bearing pins can be inserted into the bearing sleeve of a neighboring chain link. However, because of their rather complicated structure, chain links of this type are not suited for manufacture from metal.